Diphenyl-ureas,-thioureas,-guanidines and -parabanic acids

ABSTRACT

DIGUANYLHYDRAZONES OF DIPHENYL-UREAS, -THIOUREAS, -GUANIDINES AND -PARABANIC ACIDS THAT CONTAIN IN EACH OF THE TWO PHENYL RADICALS A META- OR PARA-POSITIONED ALKANECARBONYL GROUP, ABOVE ALL CORRESPOINDING DIPHENYL-UREAS, -THIOUREAS, -GUANIDINES AND -PARABANIC ACIDS THAT CONTAIN IN EACH PHYNYL RADICAL A META- OR PARA-POSITIONED ALKANECARBONYL-GUANYLHYDRAZONE GROUPING OF THE FORMULA   G-N=C(-R)-   IN WHICH G REPRESENTS A GUANIDINO GROUP AND R A LOWER ALKYL RADICAL PREFERABLY A METHYL, EHTYL, PROPYL, BUTYL OR PENTYL RADICAL, AND THEIR SALTS. THESE COMPOUNDS MAY CONTAIN FURTHER SUBSTITUENTS. THEY POSSESS TUMOUR INHIBITING ACTION AND ACT AGAINST PROTOZOAE AND AMOEBAE, ESPECIALLY AGAINST TRYPANOSOMES, FOR EXAMPLE, AGAINST TRYPANOSOMA GAMBIENSE AND TRYPANOSOMA CONGOLENSE.

United States Patent US. Cl. 260565 4 Claims ABSTRACT OF THE DISCLOSURE Diguanylhydrazones of diphenyl-ureas, -thioureas, -guanidines and -parabanic acids that contain in each of the two phenyl radicals a metaor para-positioned alkanecarbonyl group, above all corresponding diph-enyl-ureas, -thioureas, -guanidines and -parabanic acids that contain in each phenyl radical a metaor para-positioned alkanecarbonyl-guanylhydrazone grouping of the formula in which G represents a guanidino group and R a lower alkyl radical preferably a methyl, ethyl, propyl, butyl or pentyl radical, and their salts. These compounds may contain further substituents. They possess tumour inhibiting action and act against protozoae and amoebae, especially against trypanosomes, for example, against Trypanosoma gambi-ense and Trypanosoma congolense.

and

Especially it concerns diguanylhydrazones of diphenylureas, -thioureas, -guanidines and -parabanic acids that contain in each of the two phenyl radicals a meta- 0r para-positioned alkanecarbonyl group, above all corresponding diphenyl-ureas, -thioureas, -guanidines and -parabanic acids that contain in each phenyl radical a metaor para-positioned alkanecarbonylguanylhydrazone grouping of the formula R G N=(';

in which G represents a guanidino group and R is a lower alkyl radical, preferably a methyl, ethyl, propyl, butyl or pentyl radical, and their salts.

The new compounds may contain further substituents, for example on the nitrogen atoms of the guanidino group of the guanylhydrazone grouping, above all lower aliphatic hydrocarbon radicals, such as lower alkyl groups, for example those mentioned above, or in the aromatic rings, for example lower alkyl groups, such as those mentioned above, or lower alkoxy groups, for example methoxy, ethoxy, propoxy or butoxy groups, or above all halogen atoms, such as chlorine or bromine atoms, or trifiuoromethyl groups.

The new compounds possess valuable pharmacological properties, especially a tumour inhibiting action as is found in the animal test, for example on the mouse. Furthermore, the new compounds act against protozoae and amoebae, especially against trypanosomes, for example against Trypanosoma gambiense and Trypanosoma congolense. They may therefore be used as chemotherapeutics for treating tumours, as trypanocidal and amoebicidal agents. Furthermore, they may be used as intermediates, for example in the manufacture of pharmacologically active compounds.

Particularly potent are the compounds of the formula CROSS-REFERENCES TO RELATED APPLICATIONS This is a continuation-in-part of application Ser. No. 589,195, filed Oct. 25, 1966 (now abandoned).

The present invention relates to new guanylhydrazones.

II ll 00 and E 0-0 I! ll 0 O 3 in which R has the above meaning and especially para, para'-diacetyl-diphenylurea bis guanylhydrazone which, for example, in the form of its dihydrochloride dihydrate produces in leucaemic (L 1210) mice on intraperitoneal administration in doses of to mg. per kg. bodyweight a distinct life-prolonging effect.

The new compounds are obtained by known methods. Advantageously, a diphenyl-urea, -thiourea, -guanidine or -parabanic acid that contains in each of the two phenyl radicals a metaor para-positioned alkanecar-bonyl radical, such as a lower alkanecarbonyl group, for example the acetyl, propionyl, butyryl or oenanthoyl group, is reacted with a guanylhydrazine. The guanylhydrazine is advantageously used in the form of a salt thereof.

The reaction is carried out in the conventional manner.

Depending on the reaction conditions and the starting materials used the end products are obtained in the free form or in the form of their salts or, if desired, the hydrates, which are also included within the scope of the invention. The salts of the final products may be converted in a manner known per se, for example with an alkali or an ion exchanger, into the free bases. From the latter salts may be obtained by reaction with organic or inorganic acids, particularly those which are suitable for the formation of pharmaceutically acceptable salts. Suitable acids are, for example: hydrohalic acid, sulfuric acids, phosphoric acids, nitric acid; aliphatic, alicyclic, aromatic or heterocyclic carboxylic or sulfonic acids, such as formic, acetic, propionic, succinic, glycollic, lactic, malic, tartaric, citric, ascorbic, maleic, hydroxymaleic or pyruvic EXAMPLE 1 39.2 grams of aminoguanidine bicarbonate in ml. of water are mixed with 61.5 ml. of 6.17 N hydrochloric acid. The resulting solution of aminoguanidine hydrochloride is mixed with 29.63 g. of para,para-diacetyl diphenylurea and then with 200 ml. of dimethylformamide and the mixture is heated with stirring for 10 hours in an oil bath at C. The batch is filtered, concentrated in vacuo to half its original volume, and 150 ml. of water are added, the contents of the flask crystallizing. The batch is first I crystallized from ml. of dimethylformamide with the addition of 200 ml. of water, then from 100 ml. of dimethylformamide with the addition of 200 ml. of ethanol. The resulting crystals melt at 238242 C. with decomposition and are para,para-diacetyl-diphenylurea bis-guanylacid; phenylacetic, benzoic, para-aminobenzoic, anthranilic, para-hydroxybenzoic, salicylic or para-aminosalicylic, embonic, methanesulfonic, ethanesulfonic, hydroxyethanesulfonic, ethylenesulfonic acid; halogenbenzene-sulfonic, toluenesulfonic, naphthalenesulfonic acids or sulfanilic acid; methionine or tryptophan.

These or other salts of the new compounds may be used for purifying the free bases by converting the free bases into salts, separating the latter and then liberating the bases again. In view of the close relationship between the new compounds in the free form and in the form of their salts, what has been said above and herein after with reference to the free compounds refers similarly also to the corresponding salts wherever this applies.

The invention also concerns those modifications of the process in which a compound obtainable as intermediate at any stage of the process is used as starting material and the remaining process steps are carried out, or in which a starting material is formed in situ or used in the form of a salt.

The starting materials are known or, if they are new, can be prepared by a method known per se.

For the reactions of the invention such starting materials are used as yield the above-mentioned preferred compounds.

The new compounds may be used for example in the form of pharmaceutical preparations which contain them or their salts in conjunction or admixture with an organic or inorganic, solid or liquid pharmaceutical excipient suitable for enteral, parenteral or local administration. Suitable excipients are substances that do not react with the new compounds, for example water, gelatin, lactose, starches, stearyl alcohol, magnesium stearate, talcum, vegetable oils, benzyl alcohols, gums, polyalkylene-glycols, white petroleum jelly, cholesterol or other known medicinal excipients. The pharmaceutical preparations may be, for example, tablets, dragees, capsules, suppositories, ointnrcnts or creams, or in liquid form solutions, suspensions 25 g. of the dihydrochloride are poured into 1.5 liters of boiling water and stirred to give a clear solution. The solution is filtered, cooled on an ice-water bath rapidly to 30 C. and, before the dihydrochloride crystallizes out again, ml. of 2 N sodium hydroxide solution are added in one portion. The first amorphous precipitate soon becomes crystalline on cooling. The batch is suction-filtered and the precipitate washed on the filter with water and ethanol, to yield p,p'-diacetyl-diphenylurea-bisguanylhydrazone melting at 221-223 C. with decomposition.

20.42 g. (0.05 mol) of this compound are suspended in 250 ml. of absolute ethanol, and treated with 52 ml. of 2 N ethanolic methanesulfonic acid. 60 ml. of water are added successively to the suspension with heating on a water-bath until a clear solution is formed. The solution is filtered, 300 ml. of absolute ethanol are added and the product allowed to crystallize out. After filtering with suction and drying, p,p'-diacetyl diphenylurea bisguanylhydrazone bis methanesulfonate melting at 179- 183 C. is obtained. After drying in a high vacuum, the product melts at -195 C.

EXAMPLE 2 39.2 grams of aminoguanidine bicarbonate in 60 ml. of water are mixed with 60 ml. of 6.43 N-hydrochloric acid. The resulting solution of aminoguanidine hydrochloride is mixed with 29.63 g. of para,para-diacetyl diphenylurea and then with 200 ml. of dimethylformamide, and the mixture is heated with stirring for 5 hours in an oilbath at 150 C. The batch is then filtered, concentrated under vacuum to half its original volume, and 300 ml. of absolute ethanol are added, whereupon the batch turns crystalline; it is suspended in 200 ml. of water, suctionfiltered and recrystallized from 500 ml. of a 2:3-mixture of ethanol and water, while removing part of the solvent under vacuum when all has dissolved and replacing it by fresh absolute ethanol until crystallization sets in. The

crystals obtained constitute para,para'-diacetyl-diphenylurea bis guanylhydrazone dihydrochloride dihydrate which is identical with the product described in EX- ample 1.

EXAMPLE 3 19.6 grams (0.144 moi) of aminoguanidine bicarbonate are dissolved in a mixture of 30 ml. of water and 29.3 ml. (0.18 mol) of 6.15 N-hydrochloric acid. 14.85 grams suspended in 200 ml. of dimethylformamide, are added to this solution and the whole stirred for 14 hours in a bath at 50 C. The reaction mixture is filtered, the clear solution evaporated in vacuo, the residue dissolved in 250 ml. of Water, filtered again from a turbidity and al- 5 lowed to crystallize. The crystals are isolated to yield m,m diacetyl-diphenylthioureabis-guanylhydrazone dihydrochioride of the formula melting at 200-205 C. with decomposition.

EXAMPLE 6 13.18 g. of 1,3-bis-(para-acetylphenyl)-guanidine are added to a solution of aminoguanidine hydrochloride, prepared from 17.55 g. of aminoguanidine bicarbonate in ml. of water and 27.8 ml. of hydrochloric acid 1:1 (6.15

itself, whereupon gradually very finely crystalline rneta, 25 N). After addition of 90 ml. of dimethylformamide the meta-diacetyl-diphenylurea bis guanylhydrazone-dihydrochioride dihydrate of the formula CH CH3 settles out. It melts at 269 to 272 C. The water of crystallization can be removed by drying above 100 C. in a reaction mixture is stirred for 10- hours at 80 C. The clear solution is filtered and evaporated to half its volume in vacuo, 1,3-bis-(para-acetylphenyl)-guanidine-bis-guanylhydrazone trihydrochloride of the formula high vacuum. The anhydrous substance is hygroscopic and rapidly reabsorbs 2 mols of water. m,m-Diacetyldiphenylurea-bis-guanylhydrazone melting at 193 C., can be liberated from the hydrochloride by means of concentrated 1: 1 ammonia solution.

EXAMPLE 4 crystallizing out. The crystals are separated by filtration and washed with water and ethanol; M.P. 310 C.

The 1,3-bis-(para acetyl phenyl)-guanidine used as starting material may be prepared as follows:

2.5 g. of sodium are dissolved in 100 ml. of absolute ethanol. 31.24 g. of p,p'-diacetyl-diphenylthiourea, suspended in 200 ml. of ethanol, are added to the solution.

The resulting clear solution is heated for 1 hour at 90 C., then cooled to 25 C., and 14.9 g. of methyliodide in 50 m1. of ethanol are added dropwise. The batch is stirred for 5 hours in a bath at 95 C. The clear solution is filtered and ammonia gas is introduced into this solution directly for 1 hour with ice-water cooling, 1 hour at room temperature and 2 hours at 80 C. (internal temperature). The batch is cooled and filtered off from the first crystallization which is discarded, then evaporated to about 200 ml., and 1.4 liters of water are added. The

in the form of crystals melting at 212-214 C. The substance contains 1 to 2 mols of water of crystallization, depending on the degree of drying.

EXAMPLE 5 61.5 ml. of hydrochloric acid 1:1 (6.17 normal) are added to 39.2 g. of aminoguanidine bicarbonate, suspended in 60 ml. of water, to prepare a clear solution. 31.23 g. (0.1 mol) of m,m-diacetyl-diphenylthiourea,

first oily residue soon solidifies. The supernatant water is poured off and the residue allowed to stand with 300 ml. of ether. Crude 1,3 bis (para-acetylphenyl)-guanidine melting at 203-207 C. is obtained which is used directly for the above described reaction.

In an analogous manner from 1,3-bis-(meta-acetylphenyl) guanidine and aminoguanidine hydrochloride there can be obtained 1,3-bis-(meta-acetylphenyl)-guanidine-bis-guanyl-hydrazone trihydrochloride.

7 EXAMPLE 7 Tablets containing 10 mg. of p,p'-diacetyl-diphenylurea-bis-guanylhydrazone bis-hydrochloride may be prepared, for example with the following ingredients.

Ingredients per tablet: Mg.

p,p Diacetyl diphenylurea-bis-guanylhydrazone-bis-hydrochloride 10.0 Lactose 45.0 Wheat starch 20.0 Colloidal silicic acid 5.0 Arrowroot 14.5 Talc 5.0 Magnesium stearate 0.5

Method p,p'-Diacetyl-diphenylurea-bis-guanylhydrazone bis-hydrochloride is mixed with the lactose, part of the wheat starch and colloidal silicic acid and then sieved. The remaining wheat starch is pasted with five times the quantity of water on a steam-bath. With this paste the powdery mixture, possibly with the addition of water, is kneaded until a granulatable mass is formed. This mass is pressed through a sieve having a mesh of about 3 mm., dried at 45 C. and then pressed through a sieve having a mesh of 0.8 mm. Arrowroot, talc and magnesium stearate are added to the dry granulate, the resulting mixture compressed into tablets having a gross weight of 100 mg.

EXAMPLE 8 An injection solution containing mg. of p,p-diacetyl diphenylurea-bis-guanylhydrazone bis methanesulfonate may be prepared, for example, as follows:

Ingredients Mg.

p,p' Diacetyl diphenylurea-bis-guanylhydrazone-bis-methanesulfonate 10.0 Mannitol 85.0 Distilled water to make 1.0 ml.

Method The p,p'-diacetyl-diphenylurea bis guanylhydrazone bis-methanesulfonate and mannitol are dissolved in distilled water so that in 1 m1. of solution 10.0 mg. of p,pdiacetyl-diphenylurea-bis-guanylhydrazone bis methanesulfonate and 85.0 mg. of mannitol are contained. The solution is filtered through a membrane filter No. 1 and filled into ampoules while being gassed with nitrogen. The fused ampoules are heated in an autoclave at 120 C. for minutes.

EXAMPLE 9 3.50 g. of N,N'-(para,para'-diacetyl diphenyl) parabanic acid are suspended in 20 ml. of dimethylformamide. The suspension is poured into a solution of 3.92 g. of aminoguanidine bicarbonate in 6 ml. of water and 6.15 ml. of hydrochloric acid 1:1 (6.15 N). The bath is stirred for 10 hours at a bath temperature of 80 C., then allowed to cool, and filtered. There are added 100 ml. of absolute ethanol, and after some time the batch is filtered with suction. The mother liquor is evaporated under reduced pressure and the residue dissolved in 50 ml. of ethanol.

c-o II II o o In a similar manner, N,N (meta,meta diacetyl-diphenyl)-parabanic acid bis guanylhydrazone-dihydrochloride can be obtained.

The N,N'-(para,para-diacetyl diphenyl) parabanic acid used as starting material can be prepared as follows:

29.6 g. of para,para'-diacetyl-diphenylurea are suspended in 300 ml. of chloroform, the suspension treated dropwise with 14.0 g. of oxalyl chloride in 50 ml. of chloroform, and the whole stirred for 6 hours at an oil bath temperature of C. The batch is filtered with suction and the precipitate washed with chloroform and then recrystallized from ml. of dimethylformamide. The crystallizate is considerably contaminated with starting material. On addition of 100 ml. of ethanol to the mother liquor, N,N'-(para,para'-diacetyl diphenyl) parabanic acid of melting point 259262 C. is obtained.

What is claimed is:

1. A member selected from the group consisting of compounds of the formula in which G stands for guanidino, R for lower alkyl, Ph for a member selected from the group consisting of metaphenylene and para-phenylene, and Z for -NH(" -NH and their acid addition salts of pharmaceutically acceptable acids.

2. A product as claimed in claim 1, in which G stands for guanidino, R for lower alkyl, Ph for a member selected from the group consisting of meta-phenylene and para-phenylene and Z for the group of the formula 3. A product as claimed in claim 1, which product is the 1,3-bis-(para-acetylphenyl)-guanidine bis guanylhydrazone or its acid addition salt of a pharmaceutically acceptable acid.

4. A product as claimed in claim 1, which product is the 1,3-bis-(meta-acetylphenyl)-guanidine bis guanylhydrazone or its acid addition salt of a pharmaceutically acceptable acid.

References Cited UNITED STATES PATENTS 2,815,377 12/1957 Meiser, Werner et a1. 260-564 BERNARD HELFIN, Primary Examiner G. A. SCHWARTZ, Assistant Examiner US. Cl. X.R. 

